Teach Computing

Revision notes, activities, lesson plans, teaching ideas, and other resources for GCSE, A-Level, and IB Computer Science teachers and students.

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Device specifications

Device Specifications is a simple site with a huge database of smart phones...

Smart phone specs explained

This excellent site is a detailed guide to smart phone specifications, expl...

Software as a Service (Saas)

This short video gives an overview of Software as a Service (SaaS), which s...

Amazon EC2 - Elastic Cloud Server

Amazon Elastic Cloud (Amazon EC) is a good example of Infrastructure as a S...

Changeover notes

IGCSE ICT provide short but clear notes and diagrams covering the different...

CommandPoint CAD

CommandPoint by Northrop Grumman offers a range of CAD systems for various ...

CAD+911 System

TriTech Software Systems is a company that specialises in Computer Aided Di...

London Ambulance CAD failure

The 1992 London Ambulance Service CAD failure is probably the most notoriou...

Washington State 911 Failure

A 911 emergency telephone system in Washington State and Oregon shut down f...

Resources discount offer

3.1 Advanced Theory Data representation

Click here for recommended Cambridge A-Level Computer Science textbooks.

3.1.1 User-defined data types

3.1.2 File organisation and access

3.1.3 Real numbers and normalised floating-point representation

Floating point numbers

Floating point numbers

A good explanation of why we use floating point numbers. Also covers their limitations as approximations, with good explanations of floating point rounding errors applied to real-life concepts such as currency and accounting.

Updated: 2015-06-03